The present disclosure relates to a semiconductor device having an excellent interface state, a method of manufacturing the same, and a power semiconductor device including the same.
Recently, semiconductor devices are increasingly required to have high levels of performance such as fast operational speeds or low current loss.
To meet such requirements, semiconductor devices have recently tended to be formed using silicon carbide (SiC), instead of silicon (Si).
Silicon carbide (SiC) is a semiconductor material having great potential in applications related to high power, high frequency, and high temperature devices.
Silicon carbide (SiC) has a bandgap approximately three times wider and a dielectric breakdown field approximately ten times greater than silicon (Si), exhibiting excellent durability with respect to heat resistance or high voltage levels and having a significantly rapid electron drift speed.
In particular, since a dielectric breakdown field of silicon carbide (SiC) is 10 times higher than that of silicon (Si), even in the case that a depletion layer is formed to be relatively thin in a p-n junction or Schottky junction portion, a high level of breakdown voltage may be maintained.
Thus, the use of silicon carbide (SiC) may decrease a thickness of devices and increase doping concentration, such that a power semiconductor device having low ON resistance and high withstand voltage and making low loss is anticipated as being able to be realized with the use thereof.
However, it has been discovered that a metal-oxide semiconductor field effect transistor (MOSFET) semiconductor device manufactured using silicon carbide (SiC) has low carrier mobility in a channel region, as compared to a semiconductor manufactured with silicon (Si).
This is due to the fact that, in the case of forming an oxide such as silicon oxide (SiO2) on one surface of a semiconductor layer formed of silicon carbide (SiC), dangling bond or carbon (C) is extracted from an interface between the carbide silicon (SiC) and the silicon oxide (SiO2) to increase interface state density thereof.
Such an increase in interface state density leads to a reduction in carrier mobility of a semiconductor device using carbide silicon (SiC), mainly reducing performance of the semiconductor device.
Thus, in manufacturing a semiconductor device such as an MOSFET using silicon carbide (SiC), a method of lowering interface state density is required.